Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2016

Summary of Stock Based Compensation Activity Related to Nonvested RSUs

The following table summarizes activity related to nonvested RSUs:

	Number of RSUs (In thousands)		Weighted Average Grant-Date Fair Value Per Share
Nonvested at December 31, 2013		3,859		$    82.42
Granted		745		146.85
Vested		(2,194)		87.66
Forfeited		(84)		91.11
Nonvested at December 31, 2014		2,326		$    97.80
Granted		595		192.47
Vested		(1,642)		103.30
Forfeited		(43)		132.28
Nonvested at December 31, 2015		1,236		$  134.87
Granted		679		206.69
Vested		(1,009)		137.62
Forfeited		(118)		203.65
Nonvested at December 31, 2016		788		$  183.00

Stock Options

The following table pertains to stock options granted through 2012, in addition to stock options that vested and were exercised in 2016, 2015 and 2014 (in millions):

	2016		2015		2014
Grant-date fair value of all stock options that vested	$	—	$	8	$	18
Intrinsic value of all stock options exercised		172		265		297